Standard ML of New Jersey
Release Notes

Version 110.95
November 11, 2019


This release fixes a few critical problems with 110.94, as well as a couple of other bugs. There are no new features or other major changes.



64-bit support

The various installation and configuration scripts have been updated to accept a command-line argument to override the default machine size when running on the x86/amd64 architecture. For the config/ script, you can specify the machine-word size of the target architecture as follows:

-default size

specify the default size for the sml and other commands, where size is either 32 or 64.


install the 32-bit version of the system.


install the 64-bit version of the system.

It is possible to install both versions in the same location by running the script twice. For example, the commands

  % config/ -32
  % config/ -default 64

will install both versions with the 64-bit version as default. One would then use the command sml -32 to run the 32-bit version of the system.

If both versions are installed, then use the -32 or -64 flag to override the default version.

32-bit macOS issues

While the x86 installer for 110.95 works on macOs 10.14 Mojave, building from source requires some extra steps because the version of Xcode distributed for Mojave does not include a 32-bit SDK.

Another issue that you may encounter when building on macOs 10.14 Mojave is an error message for a shell script of the form

  /bin/sh: bad interpreter: Operation not permitted

This error arises because the attribute is set on the shell script. To fix the problem, remove the attribute using the command

  xattr -d shell-script

and resume the build.

Runtime System

The runtime now uses MAP_ANON for allocating memory on 64-bit Linux. This change fixes a problem with versions of Linux that do not allow access to /dev/zero.


Here is a list of tracked bugs fixed (or closed) with this release, please see the bug tracker for more details.


Real.fromString errors


segmentation fault when compiling MLton sources with SML/NJ 64-bit

The following unnumbered bugs were also fixed:

  • Fixed the AST pretty printer so that it handles datatype replication declarations.

  • Fixed problem with 64-bit runtime on some versions of Linux (e.g.. Linux on ChromeBooks).

Supported systems

We believe that SML/NJ will build and run on the following systems, but have only tested some of them:

Architecture Operating System Status


macOS 10.14 (Mojave)
macOS 10.15 (Catalina)
Ubuntu 16.04.3 LTS
Ubuntu 18.04.3 LTS


Power PC

Mac OS X 10.5 (Leopard)





x86 (32-bit)

Mac OS X 10.6 (Snow Leopard)
Mac OS X 10.7 (Lion)
Mac OS X 10.8 (Mountain Lion)
Mac OS X 10.9 (Mavericks)
Mac OS X 10.10 (Yosemite)
Mac OS X 10.11 (El Capitan)
macOS 10.12 (Sierra)
macOS 10.13 (High Sierra)
macOS 10.14 (Mojave)
Ubuntu 16.04.3 LTS
Other Linux variants
BSD variants
Windows 7
Windows 10
Cygwin (32-bit)